Not every pregnancy is planned, and those that are can take time, so it's not surprising that at some point after sperm meets egg, but before you're aware of that happy pairing, you might have enjoyed some wine with dinner or a beer at a ballgame. Cue panic, and an attempt to remember how much (and what) you imbibed. But is that panic necessary?

Try not to fretAlthough having had a couple of drinks before you knew you were pregnant isn't ideal, it is somewhat common. "Half the women in the U.S. drink alcohol and half of all pregnancies are unplanned, so there are many cases of women realizing they drank before discovering they're expecting," says Robert Sokol, M.D., professor of obstetrics and gynecology at Wayne State University School of Medicine in Detroit. It may be difficult not to worry, but do your best not dwell on the past. "Once you're pregnant, stop drinking," Dr. Sokol says.

Follow doctor's ordersIdeally, you should assess your health before becoming pregnant so you can start off your pregnancy on the best foot possible. This means taking pre-conception folic acid (400 mcg) for at least a month to reduce the chance of a neural tube defect, as well as cutting out smoking and drinking. "The earlier in pregnancy the exposure to alcohol occurs, the greater the chance of more serious damage -- so abstinence is recommended," says David Garry, D.O., a spokesperson for the American Congress of Obstetricians and Gynecologists (ACOG) and a maternal fetal medicine specialist at Montefiore Medical Center in Bronx, NY.

Of course, proper nutrition and good prenatal care are vital for a healthy pregnancy, so talk with your ob-gyn about a diet and exercise plan and be sure to take vitamins or other supplements if they are recommended.

Every pregnancy is differentNot every woman who drinks during pregnancy will bear a child with fetal alcohol syndrome. In fact, some women may have a genetic predisposition that decreases the vulnerability of their fetus to alcohol damage, and others may experience the opposite (certain women may have genes that increase the risk of an FAS-related birth). Women of advanced maternal age are in the latter category: "Older women tend to be heavier, so the more body fat one has, the faster the blood alcohol content rises because fat doesn't absorb alcohol like muscle does," Dr. Sokol says.

The bottom lineFull-blown fetal alcohol syndrome affects about 1 to 2 babies per thousand births; according to the Centers for Disease Control, scientists believe that there are at least three times as many cases of fetal alcohol spectrum disorder (FASD) as fetal alcohol syndrome. Some kids may have subtle damage that isn't even noticed until they begin school, when learning and behavior problems become apparent. So the best advice is also the simplest: For the healthiest baby, stop drinking the moment you decide you'd like to get pregnant.

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